Mobo/CPU draw

I'm looking to use a atx mobo (k7sfa) [not mini!] and an AMD Atholon XP 1500 processor for my car setup. I'll use an HD laptop drive and one DVD ROM drive. I'm planning to get an OPUS 150W supply. Does anyone think this will not work? The mobo is probably around 25watts and the CPU max is 60watts. ( I think ) Don't know about the drives, ram, ect. Or do I have to use a miniboard for a car? THanks!

I don't know if you care anymore, but I'm putting together a Celeron D 330 system running on a Keypower KP-DX250H ps (250w). Specs here - http://www.keypower.com/proddetail.a...&linenumber=15. They were one of the first ps's that handled DC-DC, and probably still the most powerful. Problem is, they are full size ATX.
I've had my machine running off a battery for around 10 minutes with no problems. I'll be installing the box in my car sometime this weekend, so I'll be sure to let everyone know if my car blows up due to overheated caps!